**Table 4:** Titan's limb-darkening parameter.
Minnaert	Range	Solar phase	Method	Reference
parameter k		angle $\alpha$
1	${\ge} 1^{c,d}$	$6^\circ25$	Lunar occultation	Elliot et al. (1975)
0.95	0.8-1.15^c	$5^\circ6$	Speckle interferometry	Nisenson et al. (1981)
0.9	0.68-1.0^a,e	$6^\circ25$	Cloud model	Smith (1980)
0.87^b	0.773-0.942^a	$29^\circ6$	Voyager 1	Sromovsky et al. (1981)
0.79^b	0.77-0.85^a	$28^\circ1$	Pioneer	Tomasko & Smith (1982)
0.90	0.83-1.15^c	$\sim$ $5^\circ5$	Modulated photometry	Present work (R=2847 km)

^a The range corresponds to different filters.
^b Calculated mean value for the Hipparcos broad-band photometric system H_p.
^c The range is given as probable values from the given technique.
^d Value of k yielding residuals within one standard deviation of the minimum.
^e The range also corresponds to different parts of the entire disc.

Source LaTeX | All tables | In the text